pvl_est_Rs_Pysch

PVL_EST_RS_PYSCH Estimate Rs using the method of Pysch.

Contents

Syntax

Description:

The method of Pysch [1] extends the Swanson method to use multiple IV curves. IV curves are assumed to be at different irradiance levels but the same cell temperature. A point is selected on each IV curve where the current is less than Isc by the input delI. If optional arguments are provided, the difference between the returned Rs value and the Rs parameter for the single diode equation is estimated, see [2].

Inputs:

Outputs:

Example

clearvars

% Set up parameters for a representative 60 cell cSi module using the Desoto model
Const.q = 1.60218E-19;
Const.k = 1.38066E-23;
Const.E0 = 1000;
Const.T0 = 25;

param.aIsc = 0.0008;  % A/C
param.bVoc = -0.1900; % V/C

param.Rs_ref = 0.2;
param.Rsh_ref = 1000;
param.IL_ref = 8.0;
param.I0_ref = 5e-10;

param.a_ref = 1.05 * 60 * Const.k/Const.q * (273.15 + Const.T0);

EgRef = 1.121;
dEgdT = -0.0002677;

% Calculate set of IV curves
Ee = 900:20:1100;
Tc = 25;
nPts = 100;
for i=1:length(Ee)
    [IL, I0, Rs, Rsh1, nNsVth] = pvl_calcparams_desoto(Ee(i), Tc, param.aIsc, param, EgRef, dEgdT);
    IVcurves(i) = pvl_singlediode(IL, I0, Rs, Rsh1, nNsVth, nPts);
end

% Current differential
STCidx = find(Ee==1000);

delI = 0.95*(IVcurves(STCidx).Isc - IVcurves(STCidx).Imp);

% Estimate Rs
Rs = pvl_est_Rs_Pysch(IVcurves, delI)
Rs =

    0.2180

References:

See also

pvl_est_Rs_Bowden , pvl_est_Rs_Swanson , pvl_est_Rs_sunsVoc , pvl_est_Rs_IEC60891_1 , pvl_est_Rs_IEC60891_2

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